Cook noodles following package directions; drain and pat dry. Combine cheeses, eggs, parsley, garlic powder, pepper and butter or margarine. Layer half of noodles, cheese mixture and spinach in buttered 9x13" baking pan; repeat layers. Sprinkle with Parmesan. Refrigerate, covered, until ready to bake. Bake, uncovered, in a 350 degree oven until bubbly (50-60 minutes). Let stand 10 minutes before cutting. Cut into squares.